xref: /openbmc/linux/arch/ia64/kernel/ptrace.c (revision edfd52e6)
1 /*
2  * Kernel support for the ptrace() and syscall tracing interfaces.
3  *
4  * Copyright (C) 1999-2005 Hewlett-Packard Co
5  *	David Mosberger-Tang <davidm@hpl.hp.com>
6  * Copyright (C) 2006 Intel Co
7  *  2006-08-12	- IA64 Native Utrace implementation support added by
8  *	Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9  *
10  * Derived from the x86 and Alpha versions.
11  */
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/mm.h>
15 #include <linux/errno.h>
16 #include <linux/ptrace.h>
17 #include <linux/user.h>
18 #include <linux/security.h>
19 #include <linux/audit.h>
20 #include <linux/signal.h>
21 #include <linux/regset.h>
22 #include <linux/elf.h>
23 #include <linux/tracehook.h>
24 
25 #include <asm/pgtable.h>
26 #include <asm/processor.h>
27 #include <asm/ptrace_offsets.h>
28 #include <asm/rse.h>
29 #include <asm/system.h>
30 #include <asm/uaccess.h>
31 #include <asm/unwind.h>
32 #ifdef CONFIG_PERFMON
33 #include <asm/perfmon.h>
34 #endif
35 
36 #include "entry.h"
37 
38 /*
39  * Bits in the PSR that we allow ptrace() to change:
40  *	be, up, ac, mfl, mfh (the user mask; five bits total)
41  *	db (debug breakpoint fault; one bit)
42  *	id (instruction debug fault disable; one bit)
43  *	dd (data debug fault disable; one bit)
44  *	ri (restart instruction; two bits)
45  *	is (instruction set; one bit)
46  */
47 #define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS	\
48 		   | IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI)
49 
50 #define MASK(nbits)	((1UL << (nbits)) - 1)	/* mask with NBITS bits set */
51 #define PFM_MASK	MASK(38)
52 
53 #define PTRACE_DEBUG	0
54 
55 #if PTRACE_DEBUG
56 # define dprintk(format...)	printk(format)
57 # define inline
58 #else
59 # define dprintk(format...)
60 #endif
61 
62 /* Return TRUE if PT was created due to kernel-entry via a system-call.  */
63 
64 static inline int
65 in_syscall (struct pt_regs *pt)
66 {
67 	return (long) pt->cr_ifs >= 0;
68 }
69 
70 /*
71  * Collect the NaT bits for r1-r31 from scratch_unat and return a NaT
72  * bitset where bit i is set iff the NaT bit of register i is set.
73  */
74 unsigned long
75 ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat)
76 {
77 #	define GET_BITS(first, last, unat)				\
78 	({								\
79 		unsigned long bit = ia64_unat_pos(&pt->r##first);	\
80 		unsigned long nbits = (last - first + 1);		\
81 		unsigned long mask = MASK(nbits) << first;		\
82 		unsigned long dist;					\
83 		if (bit < first)					\
84 			dist = 64 + bit - first;			\
85 		else							\
86 			dist = bit - first;				\
87 		ia64_rotr(unat, dist) & mask;				\
88 	})
89 	unsigned long val;
90 
91 	/*
92 	 * Registers that are stored consecutively in struct pt_regs
93 	 * can be handled in parallel.  If the register order in
94 	 * struct_pt_regs changes, this code MUST be updated.
95 	 */
96 	val  = GET_BITS( 1,  1, scratch_unat);
97 	val |= GET_BITS( 2,  3, scratch_unat);
98 	val |= GET_BITS(12, 13, scratch_unat);
99 	val |= GET_BITS(14, 14, scratch_unat);
100 	val |= GET_BITS(15, 15, scratch_unat);
101 	val |= GET_BITS( 8, 11, scratch_unat);
102 	val |= GET_BITS(16, 31, scratch_unat);
103 	return val;
104 
105 #	undef GET_BITS
106 }
107 
108 /*
109  * Set the NaT bits for the scratch registers according to NAT and
110  * return the resulting unat (assuming the scratch registers are
111  * stored in PT).
112  */
113 unsigned long
114 ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat)
115 {
116 #	define PUT_BITS(first, last, nat)				\
117 	({								\
118 		unsigned long bit = ia64_unat_pos(&pt->r##first);	\
119 		unsigned long nbits = (last - first + 1);		\
120 		unsigned long mask = MASK(nbits) << first;		\
121 		long dist;						\
122 		if (bit < first)					\
123 			dist = 64 + bit - first;			\
124 		else							\
125 			dist = bit - first;				\
126 		ia64_rotl(nat & mask, dist);				\
127 	})
128 	unsigned long scratch_unat;
129 
130 	/*
131 	 * Registers that are stored consecutively in struct pt_regs
132 	 * can be handled in parallel.  If the register order in
133 	 * struct_pt_regs changes, this code MUST be updated.
134 	 */
135 	scratch_unat  = PUT_BITS( 1,  1, nat);
136 	scratch_unat |= PUT_BITS( 2,  3, nat);
137 	scratch_unat |= PUT_BITS(12, 13, nat);
138 	scratch_unat |= PUT_BITS(14, 14, nat);
139 	scratch_unat |= PUT_BITS(15, 15, nat);
140 	scratch_unat |= PUT_BITS( 8, 11, nat);
141 	scratch_unat |= PUT_BITS(16, 31, nat);
142 
143 	return scratch_unat;
144 
145 #	undef PUT_BITS
146 }
147 
148 #define IA64_MLX_TEMPLATE	0x2
149 #define IA64_MOVL_OPCODE	6
150 
151 void
152 ia64_increment_ip (struct pt_regs *regs)
153 {
154 	unsigned long w0, ri = ia64_psr(regs)->ri + 1;
155 
156 	if (ri > 2) {
157 		ri = 0;
158 		regs->cr_iip += 16;
159 	} else if (ri == 2) {
160 		get_user(w0, (char __user *) regs->cr_iip + 0);
161 		if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
162 			/*
163 			 * rfi'ing to slot 2 of an MLX bundle causes
164 			 * an illegal operation fault.  We don't want
165 			 * that to happen...
166 			 */
167 			ri = 0;
168 			regs->cr_iip += 16;
169 		}
170 	}
171 	ia64_psr(regs)->ri = ri;
172 }
173 
174 void
175 ia64_decrement_ip (struct pt_regs *regs)
176 {
177 	unsigned long w0, ri = ia64_psr(regs)->ri - 1;
178 
179 	if (ia64_psr(regs)->ri == 0) {
180 		regs->cr_iip -= 16;
181 		ri = 2;
182 		get_user(w0, (char __user *) regs->cr_iip + 0);
183 		if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
184 			/*
185 			 * rfi'ing to slot 2 of an MLX bundle causes
186 			 * an illegal operation fault.  We don't want
187 			 * that to happen...
188 			 */
189 			ri = 1;
190 		}
191 	}
192 	ia64_psr(regs)->ri = ri;
193 }
194 
195 /*
196  * This routine is used to read an rnat bits that are stored on the
197  * kernel backing store.  Since, in general, the alignment of the user
198  * and kernel are different, this is not completely trivial.  In
199  * essence, we need to construct the user RNAT based on up to two
200  * kernel RNAT values and/or the RNAT value saved in the child's
201  * pt_regs.
202  *
203  * user rbs
204  *
205  * +--------+ <-- lowest address
206  * | slot62 |
207  * +--------+
208  * |  rnat  | 0x....1f8
209  * +--------+
210  * | slot00 | \
211  * +--------+ |
212  * | slot01 | > child_regs->ar_rnat
213  * +--------+ |
214  * | slot02 | /				kernel rbs
215  * +--------+				+--------+
216  *	    <- child_regs->ar_bspstore	| slot61 | <-- krbs
217  * +- - - - +				+--------+
218  *					| slot62 |
219  * +- - - - +				+--------+
220  *					|  rnat	 |
221  * +- - - - +				+--------+
222  *   vrnat				| slot00 |
223  * +- - - - +				+--------+
224  *					=	 =
225  *					+--------+
226  *					| slot00 | \
227  *					+--------+ |
228  *					| slot01 | > child_stack->ar_rnat
229  *					+--------+ |
230  *					| slot02 | /
231  *					+--------+
232  *						  <--- child_stack->ar_bspstore
233  *
234  * The way to think of this code is as follows: bit 0 in the user rnat
235  * corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat
236  * value.  The kernel rnat value holding this bit is stored in
237  * variable rnat0.  rnat1 is loaded with the kernel rnat value that
238  * form the upper bits of the user rnat value.
239  *
240  * Boundary cases:
241  *
242  * o when reading the rnat "below" the first rnat slot on the kernel
243  *   backing store, rnat0/rnat1 are set to 0 and the low order bits are
244  *   merged in from pt->ar_rnat.
245  *
246  * o when reading the rnat "above" the last rnat slot on the kernel
247  *   backing store, rnat0/rnat1 gets its value from sw->ar_rnat.
248  */
249 static unsigned long
250 get_rnat (struct task_struct *task, struct switch_stack *sw,
251 	  unsigned long *krbs, unsigned long *urnat_addr,
252 	  unsigned long *urbs_end)
253 {
254 	unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr;
255 	unsigned long umask = 0, mask, m;
256 	unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
257 	long num_regs, nbits;
258 	struct pt_regs *pt;
259 
260 	pt = task_pt_regs(task);
261 	kbsp = (unsigned long *) sw->ar_bspstore;
262 	ubspstore = (unsigned long *) pt->ar_bspstore;
263 
264 	if (urbs_end < urnat_addr)
265 		nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end);
266 	else
267 		nbits = 63;
268 	mask = MASK(nbits);
269 	/*
270 	 * First, figure out which bit number slot 0 in user-land maps
271 	 * to in the kernel rnat.  Do this by figuring out how many
272 	 * register slots we're beyond the user's backingstore and
273 	 * then computing the equivalent address in kernel space.
274 	 */
275 	num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
276 	slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
277 	shift = ia64_rse_slot_num(slot0_kaddr);
278 	rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
279 	rnat0_kaddr = rnat1_kaddr - 64;
280 
281 	if (ubspstore + 63 > urnat_addr) {
282 		/* some bits need to be merged in from pt->ar_rnat */
283 		umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
284 		urnat = (pt->ar_rnat & umask);
285 		mask &= ~umask;
286 		if (!mask)
287 			return urnat;
288 	}
289 
290 	m = mask << shift;
291 	if (rnat0_kaddr >= kbsp)
292 		rnat0 = sw->ar_rnat;
293 	else if (rnat0_kaddr > krbs)
294 		rnat0 = *rnat0_kaddr;
295 	urnat |= (rnat0 & m) >> shift;
296 
297 	m = mask >> (63 - shift);
298 	if (rnat1_kaddr >= kbsp)
299 		rnat1 = sw->ar_rnat;
300 	else if (rnat1_kaddr > krbs)
301 		rnat1 = *rnat1_kaddr;
302 	urnat |= (rnat1 & m) << (63 - shift);
303 	return urnat;
304 }
305 
306 /*
307  * The reverse of get_rnat.
308  */
309 static void
310 put_rnat (struct task_struct *task, struct switch_stack *sw,
311 	  unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat,
312 	  unsigned long *urbs_end)
313 {
314 	unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m;
315 	unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
316 	long num_regs, nbits;
317 	struct pt_regs *pt;
318 	unsigned long cfm, *urbs_kargs;
319 
320 	pt = task_pt_regs(task);
321 	kbsp = (unsigned long *) sw->ar_bspstore;
322 	ubspstore = (unsigned long *) pt->ar_bspstore;
323 
324 	urbs_kargs = urbs_end;
325 	if (in_syscall(pt)) {
326 		/*
327 		 * If entered via syscall, don't allow user to set rnat bits
328 		 * for syscall args.
329 		 */
330 		cfm = pt->cr_ifs;
331 		urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f));
332 	}
333 
334 	if (urbs_kargs >= urnat_addr)
335 		nbits = 63;
336 	else {
337 		if ((urnat_addr - 63) >= urbs_kargs)
338 			return;
339 		nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs);
340 	}
341 	mask = MASK(nbits);
342 
343 	/*
344 	 * First, figure out which bit number slot 0 in user-land maps
345 	 * to in the kernel rnat.  Do this by figuring out how many
346 	 * register slots we're beyond the user's backingstore and
347 	 * then computing the equivalent address in kernel space.
348 	 */
349 	num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
350 	slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
351 	shift = ia64_rse_slot_num(slot0_kaddr);
352 	rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
353 	rnat0_kaddr = rnat1_kaddr - 64;
354 
355 	if (ubspstore + 63 > urnat_addr) {
356 		/* some bits need to be place in pt->ar_rnat: */
357 		umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
358 		pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask);
359 		mask &= ~umask;
360 		if (!mask)
361 			return;
362 	}
363 	/*
364 	 * Note: Section 11.1 of the EAS guarantees that bit 63 of an
365 	 * rnat slot is ignored. so we don't have to clear it here.
366 	 */
367 	rnat0 = (urnat << shift);
368 	m = mask << shift;
369 	if (rnat0_kaddr >= kbsp)
370 		sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m);
371 	else if (rnat0_kaddr > krbs)
372 		*rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m));
373 
374 	rnat1 = (urnat >> (63 - shift));
375 	m = mask >> (63 - shift);
376 	if (rnat1_kaddr >= kbsp)
377 		sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m);
378 	else if (rnat1_kaddr > krbs)
379 		*rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m));
380 }
381 
382 static inline int
383 on_kernel_rbs (unsigned long addr, unsigned long bspstore,
384 	       unsigned long urbs_end)
385 {
386 	unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *)
387 						      urbs_end);
388 	return (addr >= bspstore && addr <= (unsigned long) rnat_addr);
389 }
390 
391 /*
392  * Read a word from the user-level backing store of task CHILD.  ADDR
393  * is the user-level address to read the word from, VAL a pointer to
394  * the return value, and USER_BSP gives the end of the user-level
395  * backing store (i.e., it's the address that would be in ar.bsp after
396  * the user executed a "cover" instruction).
397  *
398  * This routine takes care of accessing the kernel register backing
399  * store for those registers that got spilled there.  It also takes
400  * care of calculating the appropriate RNaT collection words.
401  */
402 long
403 ia64_peek (struct task_struct *child, struct switch_stack *child_stack,
404 	   unsigned long user_rbs_end, unsigned long addr, long *val)
405 {
406 	unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr;
407 	struct pt_regs *child_regs;
408 	size_t copied;
409 	long ret;
410 
411 	urbs_end = (long *) user_rbs_end;
412 	laddr = (unsigned long *) addr;
413 	child_regs = task_pt_regs(child);
414 	bspstore = (unsigned long *) child_regs->ar_bspstore;
415 	krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
416 	if (on_kernel_rbs(addr, (unsigned long) bspstore,
417 			  (unsigned long) urbs_end))
418 	{
419 		/*
420 		 * Attempt to read the RBS in an area that's actually
421 		 * on the kernel RBS => read the corresponding bits in
422 		 * the kernel RBS.
423 		 */
424 		rnat_addr = ia64_rse_rnat_addr(laddr);
425 		ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end);
426 
427 		if (laddr == rnat_addr) {
428 			/* return NaT collection word itself */
429 			*val = ret;
430 			return 0;
431 		}
432 
433 		if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) {
434 			/*
435 			 * It is implementation dependent whether the
436 			 * data portion of a NaT value gets saved on a
437 			 * st8.spill or RSE spill (e.g., see EAS 2.6,
438 			 * 4.4.4.6 Register Spill and Fill).  To get
439 			 * consistent behavior across all possible
440 			 * IA-64 implementations, we return zero in
441 			 * this case.
442 			 */
443 			*val = 0;
444 			return 0;
445 		}
446 
447 		if (laddr < urbs_end) {
448 			/*
449 			 * The desired word is on the kernel RBS and
450 			 * is not a NaT.
451 			 */
452 			regnum = ia64_rse_num_regs(bspstore, laddr);
453 			*val = *ia64_rse_skip_regs(krbs, regnum);
454 			return 0;
455 		}
456 	}
457 	copied = access_process_vm(child, addr, &ret, sizeof(ret), 0);
458 	if (copied != sizeof(ret))
459 		return -EIO;
460 	*val = ret;
461 	return 0;
462 }
463 
464 long
465 ia64_poke (struct task_struct *child, struct switch_stack *child_stack,
466 	   unsigned long user_rbs_end, unsigned long addr, long val)
467 {
468 	unsigned long *bspstore, *krbs, regnum, *laddr;
469 	unsigned long *urbs_end = (long *) user_rbs_end;
470 	struct pt_regs *child_regs;
471 
472 	laddr = (unsigned long *) addr;
473 	child_regs = task_pt_regs(child);
474 	bspstore = (unsigned long *) child_regs->ar_bspstore;
475 	krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
476 	if (on_kernel_rbs(addr, (unsigned long) bspstore,
477 			  (unsigned long) urbs_end))
478 	{
479 		/*
480 		 * Attempt to write the RBS in an area that's actually
481 		 * on the kernel RBS => write the corresponding bits
482 		 * in the kernel RBS.
483 		 */
484 		if (ia64_rse_is_rnat_slot(laddr))
485 			put_rnat(child, child_stack, krbs, laddr, val,
486 				 urbs_end);
487 		else {
488 			if (laddr < urbs_end) {
489 				regnum = ia64_rse_num_regs(bspstore, laddr);
490 				*ia64_rse_skip_regs(krbs, regnum) = val;
491 			}
492 		}
493 	} else if (access_process_vm(child, addr, &val, sizeof(val), 1)
494 		   != sizeof(val))
495 		return -EIO;
496 	return 0;
497 }
498 
499 /*
500  * Calculate the address of the end of the user-level register backing
501  * store.  This is the address that would have been stored in ar.bsp
502  * if the user had executed a "cover" instruction right before
503  * entering the kernel.  If CFMP is not NULL, it is used to return the
504  * "current frame mask" that was active at the time the kernel was
505  * entered.
506  */
507 unsigned long
508 ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt,
509 		       unsigned long *cfmp)
510 {
511 	unsigned long *krbs, *bspstore, cfm = pt->cr_ifs;
512 	long ndirty;
513 
514 	krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
515 	bspstore = (unsigned long *) pt->ar_bspstore;
516 	ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
517 
518 	if (in_syscall(pt))
519 		ndirty += (cfm & 0x7f);
520 	else
521 		cfm &= ~(1UL << 63);	/* clear valid bit */
522 
523 	if (cfmp)
524 		*cfmp = cfm;
525 	return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty);
526 }
527 
528 /*
529  * Synchronize (i.e, write) the RSE backing store living in kernel
530  * space to the VM of the CHILD task.  SW and PT are the pointers to
531  * the switch_stack and pt_regs structures, respectively.
532  * USER_RBS_END is the user-level address at which the backing store
533  * ends.
534  */
535 long
536 ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw,
537 		    unsigned long user_rbs_start, unsigned long user_rbs_end)
538 {
539 	unsigned long addr, val;
540 	long ret;
541 
542 	/* now copy word for word from kernel rbs to user rbs: */
543 	for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
544 		ret = ia64_peek(child, sw, user_rbs_end, addr, &val);
545 		if (ret < 0)
546 			return ret;
547 		if (access_process_vm(child, addr, &val, sizeof(val), 1)
548 		    != sizeof(val))
549 			return -EIO;
550 	}
551 	return 0;
552 }
553 
554 static long
555 ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw,
556 		unsigned long user_rbs_start, unsigned long user_rbs_end)
557 {
558 	unsigned long addr, val;
559 	long ret;
560 
561 	/* now copy word for word from user rbs to kernel rbs: */
562 	for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
563 		if (access_process_vm(child, addr, &val, sizeof(val), 0)
564 				!= sizeof(val))
565 			return -EIO;
566 
567 		ret = ia64_poke(child, sw, user_rbs_end, addr, val);
568 		if (ret < 0)
569 			return ret;
570 	}
571 	return 0;
572 }
573 
574 typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
575 			    unsigned long, unsigned long);
576 
577 static void do_sync_rbs(struct unw_frame_info *info, void *arg)
578 {
579 	struct pt_regs *pt;
580 	unsigned long urbs_end;
581 	syncfunc_t fn = arg;
582 
583 	if (unw_unwind_to_user(info) < 0)
584 		return;
585 	pt = task_pt_regs(info->task);
586 	urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL);
587 
588 	fn(info->task, info->sw, pt->ar_bspstore, urbs_end);
589 }
590 
591 /*
592  * when a thread is stopped (ptraced), debugger might change thread's user
593  * stack (change memory directly), and we must avoid the RSE stored in kernel
594  * to override user stack (user space's RSE is newer than kernel's in the
595  * case). To workaround the issue, we copy kernel RSE to user RSE before the
596  * task is stopped, so user RSE has updated data.  we then copy user RSE to
597  * kernel after the task is resummed from traced stop and kernel will use the
598  * newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need
599  * synchronize user RSE to kernel.
600  */
601 void ia64_ptrace_stop(void)
602 {
603 	if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
604 		return;
605 	set_notify_resume(current);
606 	unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
607 }
608 
609 /*
610  * This is called to read back the register backing store.
611  */
612 void ia64_sync_krbs(void)
613 {
614 	clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
615 
616 	unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
617 }
618 
619 /*
620  * After PTRACE_ATTACH, a thread's register backing store area in user
621  * space is assumed to contain correct data whenever the thread is
622  * stopped.  arch_ptrace_stop takes care of this on tracing stops.
623  * But if the child was already stopped for job control when we attach
624  * to it, then it might not ever get into ptrace_stop by the time we
625  * want to examine the user memory containing the RBS.
626  */
627 void
628 ptrace_attach_sync_user_rbs (struct task_struct *child)
629 {
630 	int stopped = 0;
631 	struct unw_frame_info info;
632 
633 	/*
634 	 * If the child is in TASK_STOPPED, we need to change that to
635 	 * TASK_TRACED momentarily while we operate on it.  This ensures
636 	 * that the child won't be woken up and return to user mode while
637 	 * we are doing the sync.  (It can only be woken up for SIGKILL.)
638 	 */
639 
640 	read_lock(&tasklist_lock);
641 	if (child->sighand) {
642 		spin_lock_irq(&child->sighand->siglock);
643 		if (child->state == TASK_STOPPED &&
644 		    !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
645 			set_notify_resume(child);
646 
647 			child->state = TASK_TRACED;
648 			stopped = 1;
649 		}
650 		spin_unlock_irq(&child->sighand->siglock);
651 	}
652 	read_unlock(&tasklist_lock);
653 
654 	if (!stopped)
655 		return;
656 
657 	unw_init_from_blocked_task(&info, child);
658 	do_sync_rbs(&info, ia64_sync_user_rbs);
659 
660 	/*
661 	 * Now move the child back into TASK_STOPPED if it should be in a
662 	 * job control stop, so that SIGCONT can be used to wake it up.
663 	 */
664 	read_lock(&tasklist_lock);
665 	if (child->sighand) {
666 		spin_lock_irq(&child->sighand->siglock);
667 		if (child->state == TASK_TRACED &&
668 		    (child->signal->flags & SIGNAL_STOP_STOPPED)) {
669 			child->state = TASK_STOPPED;
670 		}
671 		spin_unlock_irq(&child->sighand->siglock);
672 	}
673 	read_unlock(&tasklist_lock);
674 }
675 
676 static inline int
677 thread_matches (struct task_struct *thread, unsigned long addr)
678 {
679 	unsigned long thread_rbs_end;
680 	struct pt_regs *thread_regs;
681 
682 	if (ptrace_check_attach(thread, 0) < 0)
683 		/*
684 		 * If the thread is not in an attachable state, we'll
685 		 * ignore it.  The net effect is that if ADDR happens
686 		 * to overlap with the portion of the thread's
687 		 * register backing store that is currently residing
688 		 * on the thread's kernel stack, then ptrace() may end
689 		 * up accessing a stale value.  But if the thread
690 		 * isn't stopped, that's a problem anyhow, so we're
691 		 * doing as well as we can...
692 		 */
693 		return 0;
694 
695 	thread_regs = task_pt_regs(thread);
696 	thread_rbs_end = ia64_get_user_rbs_end(thread, thread_regs, NULL);
697 	if (!on_kernel_rbs(addr, thread_regs->ar_bspstore, thread_rbs_end))
698 		return 0;
699 
700 	return 1;	/* looks like we've got a winner */
701 }
702 
703 /*
704  * Write f32-f127 back to task->thread.fph if it has been modified.
705  */
706 inline void
707 ia64_flush_fph (struct task_struct *task)
708 {
709 	struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
710 
711 	/*
712 	 * Prevent migrating this task while
713 	 * we're fiddling with the FPU state
714 	 */
715 	preempt_disable();
716 	if (ia64_is_local_fpu_owner(task) && psr->mfh) {
717 		psr->mfh = 0;
718 		task->thread.flags |= IA64_THREAD_FPH_VALID;
719 		ia64_save_fpu(&task->thread.fph[0]);
720 	}
721 	preempt_enable();
722 }
723 
724 /*
725  * Sync the fph state of the task so that it can be manipulated
726  * through thread.fph.  If necessary, f32-f127 are written back to
727  * thread.fph or, if the fph state hasn't been used before, thread.fph
728  * is cleared to zeroes.  Also, access to f32-f127 is disabled to
729  * ensure that the task picks up the state from thread.fph when it
730  * executes again.
731  */
732 void
733 ia64_sync_fph (struct task_struct *task)
734 {
735 	struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
736 
737 	ia64_flush_fph(task);
738 	if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
739 		task->thread.flags |= IA64_THREAD_FPH_VALID;
740 		memset(&task->thread.fph, 0, sizeof(task->thread.fph));
741 	}
742 	ia64_drop_fpu(task);
743 	psr->dfh = 1;
744 }
745 
746 /*
747  * Change the machine-state of CHILD such that it will return via the normal
748  * kernel exit-path, rather than the syscall-exit path.
749  */
750 static void
751 convert_to_non_syscall (struct task_struct *child, struct pt_regs  *pt,
752 			unsigned long cfm)
753 {
754 	struct unw_frame_info info, prev_info;
755 	unsigned long ip, sp, pr;
756 
757 	unw_init_from_blocked_task(&info, child);
758 	while (1) {
759 		prev_info = info;
760 		if (unw_unwind(&info) < 0)
761 			return;
762 
763 		unw_get_sp(&info, &sp);
764 		if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
765 		    < IA64_PT_REGS_SIZE) {
766 			dprintk("ptrace.%s: ran off the top of the kernel "
767 				"stack\n", __func__);
768 			return;
769 		}
770 		if (unw_get_pr (&prev_info, &pr) < 0) {
771 			unw_get_rp(&prev_info, &ip);
772 			dprintk("ptrace.%s: failed to read "
773 				"predicate register (ip=0x%lx)\n",
774 				__func__, ip);
775 			return;
776 		}
777 		if (unw_is_intr_frame(&info)
778 		    && (pr & (1UL << PRED_USER_STACK)))
779 			break;
780 	}
781 
782 	/*
783 	 * Note: at the time of this call, the target task is blocked
784 	 * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
785 	 * (aka, "pLvSys") we redirect execution from
786 	 * .work_pending_syscall_end to .work_processed_kernel.
787 	 */
788 	unw_get_pr(&prev_info, &pr);
789 	pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
790 	pr |=  (1UL << PRED_NON_SYSCALL);
791 	unw_set_pr(&prev_info, pr);
792 
793 	pt->cr_ifs = (1UL << 63) | cfm;
794 	/*
795 	 * Clear the memory that is NOT written on syscall-entry to
796 	 * ensure we do not leak kernel-state to user when execution
797 	 * resumes.
798 	 */
799 	pt->r2 = 0;
800 	pt->r3 = 0;
801 	pt->r14 = 0;
802 	memset(&pt->r16, 0, 16*8);	/* clear r16-r31 */
803 	memset(&pt->f6, 0, 6*16);	/* clear f6-f11 */
804 	pt->b7 = 0;
805 	pt->ar_ccv = 0;
806 	pt->ar_csd = 0;
807 	pt->ar_ssd = 0;
808 }
809 
810 static int
811 access_nat_bits (struct task_struct *child, struct pt_regs *pt,
812 		 struct unw_frame_info *info,
813 		 unsigned long *data, int write_access)
814 {
815 	unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
816 	char nat = 0;
817 
818 	if (write_access) {
819 		nat_bits = *data;
820 		scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
821 		if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
822 			dprintk("ptrace: failed to set ar.unat\n");
823 			return -1;
824 		}
825 		for (regnum = 4; regnum <= 7; ++regnum) {
826 			unw_get_gr(info, regnum, &dummy, &nat);
827 			unw_set_gr(info, regnum, dummy,
828 				   (nat_bits >> regnum) & 1);
829 		}
830 	} else {
831 		if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
832 			dprintk("ptrace: failed to read ar.unat\n");
833 			return -1;
834 		}
835 		nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
836 		for (regnum = 4; regnum <= 7; ++regnum) {
837 			unw_get_gr(info, regnum, &dummy, &nat);
838 			nat_bits |= (nat != 0) << regnum;
839 		}
840 		*data = nat_bits;
841 	}
842 	return 0;
843 }
844 
845 static int
846 access_uarea (struct task_struct *child, unsigned long addr,
847 	      unsigned long *data, int write_access);
848 
849 static long
850 ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
851 {
852 	unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
853 	struct unw_frame_info info;
854 	struct ia64_fpreg fpval;
855 	struct switch_stack *sw;
856 	struct pt_regs *pt;
857 	long ret, retval = 0;
858 	char nat = 0;
859 	int i;
860 
861 	if (!access_ok(VERIFY_WRITE, ppr, sizeof(struct pt_all_user_regs)))
862 		return -EIO;
863 
864 	pt = task_pt_regs(child);
865 	sw = (struct switch_stack *) (child->thread.ksp + 16);
866 	unw_init_from_blocked_task(&info, child);
867 	if (unw_unwind_to_user(&info) < 0) {
868 		return -EIO;
869 	}
870 
871 	if (((unsigned long) ppr & 0x7) != 0) {
872 		dprintk("ptrace:unaligned register address %p\n", ppr);
873 		return -EIO;
874 	}
875 
876 	if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0
877 	    || access_uarea(child, PT_AR_EC, &ec, 0) < 0
878 	    || access_uarea(child, PT_AR_LC, &lc, 0) < 0
879 	    || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0
880 	    || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0
881 	    || access_uarea(child, PT_CFM, &cfm, 0)
882 	    || access_uarea(child, PT_NAT_BITS, &nat_bits, 0))
883 		return -EIO;
884 
885 	/* control regs */
886 
887 	retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
888 	retval |= __put_user(psr, &ppr->cr_ipsr);
889 
890 	/* app regs */
891 
892 	retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
893 	retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
894 	retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
895 	retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
896 	retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
897 	retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
898 
899 	retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
900 	retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
901 	retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
902 	retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
903 	retval |= __put_user(cfm, &ppr->cfm);
904 
905 	/* gr1-gr3 */
906 
907 	retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
908 	retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
909 
910 	/* gr4-gr7 */
911 
912 	for (i = 4; i < 8; i++) {
913 		if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
914 			return -EIO;
915 		retval |= __put_user(val, &ppr->gr[i]);
916 	}
917 
918 	/* gr8-gr11 */
919 
920 	retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
921 
922 	/* gr12-gr15 */
923 
924 	retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
925 	retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
926 	retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
927 
928 	/* gr16-gr31 */
929 
930 	retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
931 
932 	/* b0 */
933 
934 	retval |= __put_user(pt->b0, &ppr->br[0]);
935 
936 	/* b1-b5 */
937 
938 	for (i = 1; i < 6; i++) {
939 		if (unw_access_br(&info, i, &val, 0) < 0)
940 			return -EIO;
941 		__put_user(val, &ppr->br[i]);
942 	}
943 
944 	/* b6-b7 */
945 
946 	retval |= __put_user(pt->b6, &ppr->br[6]);
947 	retval |= __put_user(pt->b7, &ppr->br[7]);
948 
949 	/* fr2-fr5 */
950 
951 	for (i = 2; i < 6; i++) {
952 		if (unw_get_fr(&info, i, &fpval) < 0)
953 			return -EIO;
954 		retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
955 	}
956 
957 	/* fr6-fr11 */
958 
959 	retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
960 				 sizeof(struct ia64_fpreg) * 6);
961 
962 	/* fp scratch regs(12-15) */
963 
964 	retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
965 				 sizeof(struct ia64_fpreg) * 4);
966 
967 	/* fr16-fr31 */
968 
969 	for (i = 16; i < 32; i++) {
970 		if (unw_get_fr(&info, i, &fpval) < 0)
971 			return -EIO;
972 		retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
973 	}
974 
975 	/* fph */
976 
977 	ia64_flush_fph(child);
978 	retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
979 				 sizeof(ppr->fr[32]) * 96);
980 
981 	/*  preds */
982 
983 	retval |= __put_user(pt->pr, &ppr->pr);
984 
985 	/* nat bits */
986 
987 	retval |= __put_user(nat_bits, &ppr->nat);
988 
989 	ret = retval ? -EIO : 0;
990 	return ret;
991 }
992 
993 static long
994 ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
995 {
996 	unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
997 	struct unw_frame_info info;
998 	struct switch_stack *sw;
999 	struct ia64_fpreg fpval;
1000 	struct pt_regs *pt;
1001 	long ret, retval = 0;
1002 	int i;
1003 
1004 	memset(&fpval, 0, sizeof(fpval));
1005 
1006 	if (!access_ok(VERIFY_READ, ppr, sizeof(struct pt_all_user_regs)))
1007 		return -EIO;
1008 
1009 	pt = task_pt_regs(child);
1010 	sw = (struct switch_stack *) (child->thread.ksp + 16);
1011 	unw_init_from_blocked_task(&info, child);
1012 	if (unw_unwind_to_user(&info) < 0) {
1013 		return -EIO;
1014 	}
1015 
1016 	if (((unsigned long) ppr & 0x7) != 0) {
1017 		dprintk("ptrace:unaligned register address %p\n", ppr);
1018 		return -EIO;
1019 	}
1020 
1021 	/* control regs */
1022 
1023 	retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
1024 	retval |= __get_user(psr, &ppr->cr_ipsr);
1025 
1026 	/* app regs */
1027 
1028 	retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1029 	retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
1030 	retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1031 	retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1032 	retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1033 	retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1034 
1035 	retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
1036 	retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
1037 	retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1038 	retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
1039 	retval |= __get_user(cfm, &ppr->cfm);
1040 
1041 	/* gr1-gr3 */
1042 
1043 	retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
1044 	retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
1045 
1046 	/* gr4-gr7 */
1047 
1048 	for (i = 4; i < 8; i++) {
1049 		retval |= __get_user(val, &ppr->gr[i]);
1050 		/* NaT bit will be set via PT_NAT_BITS: */
1051 		if (unw_set_gr(&info, i, val, 0) < 0)
1052 			return -EIO;
1053 	}
1054 
1055 	/* gr8-gr11 */
1056 
1057 	retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
1058 
1059 	/* gr12-gr15 */
1060 
1061 	retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
1062 	retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
1063 	retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
1064 
1065 	/* gr16-gr31 */
1066 
1067 	retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
1068 
1069 	/* b0 */
1070 
1071 	retval |= __get_user(pt->b0, &ppr->br[0]);
1072 
1073 	/* b1-b5 */
1074 
1075 	for (i = 1; i < 6; i++) {
1076 		retval |= __get_user(val, &ppr->br[i]);
1077 		unw_set_br(&info, i, val);
1078 	}
1079 
1080 	/* b6-b7 */
1081 
1082 	retval |= __get_user(pt->b6, &ppr->br[6]);
1083 	retval |= __get_user(pt->b7, &ppr->br[7]);
1084 
1085 	/* fr2-fr5 */
1086 
1087 	for (i = 2; i < 6; i++) {
1088 		retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
1089 		if (unw_set_fr(&info, i, fpval) < 0)
1090 			return -EIO;
1091 	}
1092 
1093 	/* fr6-fr11 */
1094 
1095 	retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
1096 				   sizeof(ppr->fr[6]) * 6);
1097 
1098 	/* fp scratch regs(12-15) */
1099 
1100 	retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
1101 				   sizeof(ppr->fr[12]) * 4);
1102 
1103 	/* fr16-fr31 */
1104 
1105 	for (i = 16; i < 32; i++) {
1106 		retval |= __copy_from_user(&fpval, &ppr->fr[i],
1107 					   sizeof(fpval));
1108 		if (unw_set_fr(&info, i, fpval) < 0)
1109 			return -EIO;
1110 	}
1111 
1112 	/* fph */
1113 
1114 	ia64_sync_fph(child);
1115 	retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
1116 				   sizeof(ppr->fr[32]) * 96);
1117 
1118 	/* preds */
1119 
1120 	retval |= __get_user(pt->pr, &ppr->pr);
1121 
1122 	/* nat bits */
1123 
1124 	retval |= __get_user(nat_bits, &ppr->nat);
1125 
1126 	retval |= access_uarea(child, PT_CR_IPSR, &psr, 1);
1127 	retval |= access_uarea(child, PT_AR_RSC, &rsc, 1);
1128 	retval |= access_uarea(child, PT_AR_EC, &ec, 1);
1129 	retval |= access_uarea(child, PT_AR_LC, &lc, 1);
1130 	retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1);
1131 	retval |= access_uarea(child, PT_AR_BSP, &bsp, 1);
1132 	retval |= access_uarea(child, PT_CFM, &cfm, 1);
1133 	retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1);
1134 
1135 	ret = retval ? -EIO : 0;
1136 	return ret;
1137 }
1138 
1139 void
1140 user_enable_single_step (struct task_struct *child)
1141 {
1142 	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1143 
1144 	set_tsk_thread_flag(child, TIF_SINGLESTEP);
1145 	child_psr->ss = 1;
1146 }
1147 
1148 void
1149 user_enable_block_step (struct task_struct *child)
1150 {
1151 	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1152 
1153 	set_tsk_thread_flag(child, TIF_SINGLESTEP);
1154 	child_psr->tb = 1;
1155 }
1156 
1157 void
1158 user_disable_single_step (struct task_struct *child)
1159 {
1160 	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1161 
1162 	/* make sure the single step/taken-branch trap bits are not set: */
1163 	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1164 	child_psr->ss = 0;
1165 	child_psr->tb = 0;
1166 }
1167 
1168 /*
1169  * Called by kernel/ptrace.c when detaching..
1170  *
1171  * Make sure the single step bit is not set.
1172  */
1173 void
1174 ptrace_disable (struct task_struct *child)
1175 {
1176 	user_disable_single_step(child);
1177 }
1178 
1179 long
1180 arch_ptrace (struct task_struct *child, long request,
1181 	     unsigned long addr, unsigned long data)
1182 {
1183 	switch (request) {
1184 	case PTRACE_PEEKTEXT:
1185 	case PTRACE_PEEKDATA:
1186 		/* read word at location addr */
1187 		if (access_process_vm(child, addr, &data, sizeof(data), 0)
1188 		    != sizeof(data))
1189 			return -EIO;
1190 		/* ensure return value is not mistaken for error code */
1191 		force_successful_syscall_return();
1192 		return data;
1193 
1194 	/* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
1195 	 * by the generic ptrace_request().
1196 	 */
1197 
1198 	case PTRACE_PEEKUSR:
1199 		/* read the word at addr in the USER area */
1200 		if (access_uarea(child, addr, &data, 0) < 0)
1201 			return -EIO;
1202 		/* ensure return value is not mistaken for error code */
1203 		force_successful_syscall_return();
1204 		return data;
1205 
1206 	case PTRACE_POKEUSR:
1207 		/* write the word at addr in the USER area */
1208 		if (access_uarea(child, addr, &data, 1) < 0)
1209 			return -EIO;
1210 		return 0;
1211 
1212 	case PTRACE_OLD_GETSIGINFO:
1213 		/* for backwards-compatibility */
1214 		return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
1215 
1216 	case PTRACE_OLD_SETSIGINFO:
1217 		/* for backwards-compatibility */
1218 		return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
1219 
1220 	case PTRACE_GETREGS:
1221 		return ptrace_getregs(child,
1222 				      (struct pt_all_user_regs __user *) data);
1223 
1224 	case PTRACE_SETREGS:
1225 		return ptrace_setregs(child,
1226 				      (struct pt_all_user_regs __user *) data);
1227 
1228 	default:
1229 		return ptrace_request(child, request, addr, data);
1230 	}
1231 }
1232 
1233 
1234 /* "asmlinkage" so the input arguments are preserved... */
1235 
1236 asmlinkage long
1237 syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
1238 		     long arg4, long arg5, long arg6, long arg7,
1239 		     struct pt_regs regs)
1240 {
1241 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1242 		if (tracehook_report_syscall_entry(&regs))
1243 			return -ENOSYS;
1244 
1245 	/* copy user rbs to kernel rbs */
1246 	if (test_thread_flag(TIF_RESTORE_RSE))
1247 		ia64_sync_krbs();
1248 
1249 	if (unlikely(current->audit_context)) {
1250 		long syscall;
1251 		int arch;
1252 
1253 		syscall = regs.r15;
1254 		arch = AUDIT_ARCH_IA64;
1255 
1256 		audit_syscall_entry(arch, syscall, arg0, arg1, arg2, arg3);
1257 	}
1258 
1259 	return 0;
1260 }
1261 
1262 /* "asmlinkage" so the input arguments are preserved... */
1263 
1264 asmlinkage void
1265 syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
1266 		     long arg4, long arg5, long arg6, long arg7,
1267 		     struct pt_regs regs)
1268 {
1269 	int step;
1270 
1271 	if (unlikely(current->audit_context)) {
1272 		int success = AUDITSC_RESULT(regs.r10);
1273 		long result = regs.r8;
1274 
1275 		if (success != AUDITSC_SUCCESS)
1276 			result = -result;
1277 		audit_syscall_exit(success, result);
1278 	}
1279 
1280 	step = test_thread_flag(TIF_SINGLESTEP);
1281 	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
1282 		tracehook_report_syscall_exit(&regs, step);
1283 
1284 	/* copy user rbs to kernel rbs */
1285 	if (test_thread_flag(TIF_RESTORE_RSE))
1286 		ia64_sync_krbs();
1287 }
1288 
1289 /* Utrace implementation starts here */
1290 struct regset_get {
1291 	void *kbuf;
1292 	void __user *ubuf;
1293 };
1294 
1295 struct regset_set {
1296 	const void *kbuf;
1297 	const void __user *ubuf;
1298 };
1299 
1300 struct regset_getset {
1301 	struct task_struct *target;
1302 	const struct user_regset *regset;
1303 	union {
1304 		struct regset_get get;
1305 		struct regset_set set;
1306 	} u;
1307 	unsigned int pos;
1308 	unsigned int count;
1309 	int ret;
1310 };
1311 
1312 static int
1313 access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info,
1314 		unsigned long addr, unsigned long *data, int write_access)
1315 {
1316 	struct pt_regs *pt;
1317 	unsigned long *ptr = NULL;
1318 	int ret;
1319 	char nat = 0;
1320 
1321 	pt = task_pt_regs(target);
1322 	switch (addr) {
1323 	case ELF_GR_OFFSET(1):
1324 		ptr = &pt->r1;
1325 		break;
1326 	case ELF_GR_OFFSET(2):
1327 	case ELF_GR_OFFSET(3):
1328 		ptr = (void *)&pt->r2 + (addr - ELF_GR_OFFSET(2));
1329 		break;
1330 	case ELF_GR_OFFSET(4) ... ELF_GR_OFFSET(7):
1331 		if (write_access) {
1332 			/* read NaT bit first: */
1333 			unsigned long dummy;
1334 
1335 			ret = unw_get_gr(info, addr/8, &dummy, &nat);
1336 			if (ret < 0)
1337 				return ret;
1338 		}
1339 		return unw_access_gr(info, addr/8, data, &nat, write_access);
1340 	case ELF_GR_OFFSET(8) ... ELF_GR_OFFSET(11):
1341 		ptr = (void *)&pt->r8 + addr - ELF_GR_OFFSET(8);
1342 		break;
1343 	case ELF_GR_OFFSET(12):
1344 	case ELF_GR_OFFSET(13):
1345 		ptr = (void *)&pt->r12 + addr - ELF_GR_OFFSET(12);
1346 		break;
1347 	case ELF_GR_OFFSET(14):
1348 		ptr = &pt->r14;
1349 		break;
1350 	case ELF_GR_OFFSET(15):
1351 		ptr = &pt->r15;
1352 	}
1353 	if (write_access)
1354 		*ptr = *data;
1355 	else
1356 		*data = *ptr;
1357 	return 0;
1358 }
1359 
1360 static int
1361 access_elf_breg(struct task_struct *target, struct unw_frame_info *info,
1362 		unsigned long addr, unsigned long *data, int write_access)
1363 {
1364 	struct pt_regs *pt;
1365 	unsigned long *ptr = NULL;
1366 
1367 	pt = task_pt_regs(target);
1368 	switch (addr) {
1369 	case ELF_BR_OFFSET(0):
1370 		ptr = &pt->b0;
1371 		break;
1372 	case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5):
1373 		return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8,
1374 				     data, write_access);
1375 	case ELF_BR_OFFSET(6):
1376 		ptr = &pt->b6;
1377 		break;
1378 	case ELF_BR_OFFSET(7):
1379 		ptr = &pt->b7;
1380 	}
1381 	if (write_access)
1382 		*ptr = *data;
1383 	else
1384 		*data = *ptr;
1385 	return 0;
1386 }
1387 
1388 static int
1389 access_elf_areg(struct task_struct *target, struct unw_frame_info *info,
1390 		unsigned long addr, unsigned long *data, int write_access)
1391 {
1392 	struct pt_regs *pt;
1393 	unsigned long cfm, urbs_end;
1394 	unsigned long *ptr = NULL;
1395 
1396 	pt = task_pt_regs(target);
1397 	if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) {
1398 		switch (addr) {
1399 		case ELF_AR_RSC_OFFSET:
1400 			/* force PL3 */
1401 			if (write_access)
1402 				pt->ar_rsc = *data | (3 << 2);
1403 			else
1404 				*data = pt->ar_rsc;
1405 			return 0;
1406 		case ELF_AR_BSP_OFFSET:
1407 			/*
1408 			 * By convention, we use PT_AR_BSP to refer to
1409 			 * the end of the user-level backing store.
1410 			 * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
1411 			 * to get the real value of ar.bsp at the time
1412 			 * the kernel was entered.
1413 			 *
1414 			 * Furthermore, when changing the contents of
1415 			 * PT_AR_BSP (or PT_CFM) while the task is
1416 			 * blocked in a system call, convert the state
1417 			 * so that the non-system-call exit
1418 			 * path is used.  This ensures that the proper
1419 			 * state will be picked up when resuming
1420 			 * execution.  However, it *also* means that
1421 			 * once we write PT_AR_BSP/PT_CFM, it won't be
1422 			 * possible to modify the syscall arguments of
1423 			 * the pending system call any longer.  This
1424 			 * shouldn't be an issue because modifying
1425 			 * PT_AR_BSP/PT_CFM generally implies that
1426 			 * we're either abandoning the pending system
1427 			 * call or that we defer it's re-execution
1428 			 * (e.g., due to GDB doing an inferior
1429 			 * function call).
1430 			 */
1431 			urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1432 			if (write_access) {
1433 				if (*data != urbs_end) {
1434 					if (in_syscall(pt))
1435 						convert_to_non_syscall(target,
1436 								       pt,
1437 								       cfm);
1438 					/*
1439 					 * Simulate user-level write
1440 					 * of ar.bsp:
1441 					 */
1442 					pt->loadrs = 0;
1443 					pt->ar_bspstore = *data;
1444 				}
1445 			} else
1446 				*data = urbs_end;
1447 			return 0;
1448 		case ELF_AR_BSPSTORE_OFFSET:
1449 			ptr = &pt->ar_bspstore;
1450 			break;
1451 		case ELF_AR_RNAT_OFFSET:
1452 			ptr = &pt->ar_rnat;
1453 			break;
1454 		case ELF_AR_CCV_OFFSET:
1455 			ptr = &pt->ar_ccv;
1456 			break;
1457 		case ELF_AR_UNAT_OFFSET:
1458 			ptr = &pt->ar_unat;
1459 			break;
1460 		case ELF_AR_FPSR_OFFSET:
1461 			ptr = &pt->ar_fpsr;
1462 			break;
1463 		case ELF_AR_PFS_OFFSET:
1464 			ptr = &pt->ar_pfs;
1465 			break;
1466 		case ELF_AR_LC_OFFSET:
1467 			return unw_access_ar(info, UNW_AR_LC, data,
1468 					     write_access);
1469 		case ELF_AR_EC_OFFSET:
1470 			return unw_access_ar(info, UNW_AR_EC, data,
1471 					     write_access);
1472 		case ELF_AR_CSD_OFFSET:
1473 			ptr = &pt->ar_csd;
1474 			break;
1475 		case ELF_AR_SSD_OFFSET:
1476 			ptr = &pt->ar_ssd;
1477 		}
1478 	} else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) {
1479 		switch (addr) {
1480 		case ELF_CR_IIP_OFFSET:
1481 			ptr = &pt->cr_iip;
1482 			break;
1483 		case ELF_CFM_OFFSET:
1484 			urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1485 			if (write_access) {
1486 				if (((cfm ^ *data) & PFM_MASK) != 0) {
1487 					if (in_syscall(pt))
1488 						convert_to_non_syscall(target,
1489 								       pt,
1490 								       cfm);
1491 					pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
1492 						      | (*data & PFM_MASK));
1493 				}
1494 			} else
1495 				*data = cfm;
1496 			return 0;
1497 		case ELF_CR_IPSR_OFFSET:
1498 			if (write_access) {
1499 				unsigned long tmp = *data;
1500 				/* psr.ri==3 is a reserved value: SDM 2:25 */
1501 				if ((tmp & IA64_PSR_RI) == IA64_PSR_RI)
1502 					tmp &= ~IA64_PSR_RI;
1503 				pt->cr_ipsr = ((tmp & IPSR_MASK)
1504 					       | (pt->cr_ipsr & ~IPSR_MASK));
1505 			} else
1506 				*data = (pt->cr_ipsr & IPSR_MASK);
1507 			return 0;
1508 		}
1509 	} else if (addr == ELF_NAT_OFFSET)
1510 		return access_nat_bits(target, pt, info,
1511 				       data, write_access);
1512 	else if (addr == ELF_PR_OFFSET)
1513 		ptr = &pt->pr;
1514 	else
1515 		return -1;
1516 
1517 	if (write_access)
1518 		*ptr = *data;
1519 	else
1520 		*data = *ptr;
1521 
1522 	return 0;
1523 }
1524 
1525 static int
1526 access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
1527 		unsigned long addr, unsigned long *data, int write_access)
1528 {
1529 	if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(15))
1530 		return access_elf_gpreg(target, info, addr, data, write_access);
1531 	else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7))
1532 		return access_elf_breg(target, info, addr, data, write_access);
1533 	else
1534 		return access_elf_areg(target, info, addr, data, write_access);
1535 }
1536 
1537 void do_gpregs_get(struct unw_frame_info *info, void *arg)
1538 {
1539 	struct pt_regs *pt;
1540 	struct regset_getset *dst = arg;
1541 	elf_greg_t tmp[16];
1542 	unsigned int i, index, min_copy;
1543 
1544 	if (unw_unwind_to_user(info) < 0)
1545 		return;
1546 
1547 	/*
1548 	 * coredump format:
1549 	 *      r0-r31
1550 	 *      NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
1551 	 *      predicate registers (p0-p63)
1552 	 *      b0-b7
1553 	 *      ip cfm user-mask
1554 	 *      ar.rsc ar.bsp ar.bspstore ar.rnat
1555 	 *      ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
1556 	 */
1557 
1558 
1559 	/* Skip r0 */
1560 	if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1561 		dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1562 						      &dst->u.get.kbuf,
1563 						      &dst->u.get.ubuf,
1564 						      0, ELF_GR_OFFSET(1));
1565 		if (dst->ret || dst->count == 0)
1566 			return;
1567 	}
1568 
1569 	/* gr1 - gr15 */
1570 	if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1571 		index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1572 		min_copy = ELF_GR_OFFSET(16) > (dst->pos + dst->count) ?
1573 			 (dst->pos + dst->count) : ELF_GR_OFFSET(16);
1574 		for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1575 				index++)
1576 			if (access_elf_reg(dst->target, info, i,
1577 						&tmp[index], 0) < 0) {
1578 				dst->ret = -EIO;
1579 				return;
1580 			}
1581 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1582 				&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1583 				ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1584 		if (dst->ret || dst->count == 0)
1585 			return;
1586 	}
1587 
1588 	/* r16-r31 */
1589 	if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1590 		pt = task_pt_regs(dst->target);
1591 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1592 				&dst->u.get.kbuf, &dst->u.get.ubuf, &pt->r16,
1593 				ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1594 		if (dst->ret || dst->count == 0)
1595 			return;
1596 	}
1597 
1598 	/* nat, pr, b0 - b7 */
1599 	if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1600 		index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1601 		min_copy = ELF_CR_IIP_OFFSET > (dst->pos + dst->count) ?
1602 			 (dst->pos + dst->count) : ELF_CR_IIP_OFFSET;
1603 		for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1604 				index++)
1605 			if (access_elf_reg(dst->target, info, i,
1606 						&tmp[index], 0) < 0) {
1607 				dst->ret = -EIO;
1608 				return;
1609 			}
1610 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1611 				&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1612 				ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1613 		if (dst->ret || dst->count == 0)
1614 			return;
1615 	}
1616 
1617 	/* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1618 	 * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1619 	 */
1620 	if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1621 		index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1622 		min_copy = ELF_AR_END_OFFSET > (dst->pos + dst->count) ?
1623 			 (dst->pos + dst->count) : ELF_AR_END_OFFSET;
1624 		for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1625 				index++)
1626 			if (access_elf_reg(dst->target, info, i,
1627 						&tmp[index], 0) < 0) {
1628 				dst->ret = -EIO;
1629 				return;
1630 			}
1631 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1632 				&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1633 				ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1634 	}
1635 }
1636 
1637 void do_gpregs_set(struct unw_frame_info *info, void *arg)
1638 {
1639 	struct pt_regs *pt;
1640 	struct regset_getset *dst = arg;
1641 	elf_greg_t tmp[16];
1642 	unsigned int i, index;
1643 
1644 	if (unw_unwind_to_user(info) < 0)
1645 		return;
1646 
1647 	/* Skip r0 */
1648 	if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1649 		dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1650 						       &dst->u.set.kbuf,
1651 						       &dst->u.set.ubuf,
1652 						       0, ELF_GR_OFFSET(1));
1653 		if (dst->ret || dst->count == 0)
1654 			return;
1655 	}
1656 
1657 	/* gr1-gr15 */
1658 	if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1659 		i = dst->pos;
1660 		index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1661 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1662 				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1663 				ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1664 		if (dst->ret)
1665 			return;
1666 		for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1667 			if (access_elf_reg(dst->target, info, i,
1668 						&tmp[index], 1) < 0) {
1669 				dst->ret = -EIO;
1670 				return;
1671 			}
1672 		if (dst->count == 0)
1673 			return;
1674 	}
1675 
1676 	/* gr16-gr31 */
1677 	if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1678 		pt = task_pt_regs(dst->target);
1679 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1680 				&dst->u.set.kbuf, &dst->u.set.ubuf, &pt->r16,
1681 				ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1682 		if (dst->ret || dst->count == 0)
1683 			return;
1684 	}
1685 
1686 	/* nat, pr, b0 - b7 */
1687 	if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1688 		i = dst->pos;
1689 		index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1690 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1691 				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1692 				ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1693 		if (dst->ret)
1694 			return;
1695 		for (; i < dst->pos; i += sizeof(elf_greg_t), index++)
1696 			if (access_elf_reg(dst->target, info, i,
1697 						&tmp[index], 1) < 0) {
1698 				dst->ret = -EIO;
1699 				return;
1700 			}
1701 		if (dst->count == 0)
1702 			return;
1703 	}
1704 
1705 	/* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1706 	 * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1707 	 */
1708 	if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1709 		i = dst->pos;
1710 		index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1711 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1712 				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1713 				ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1714 		if (dst->ret)
1715 			return;
1716 		for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1717 			if (access_elf_reg(dst->target, info, i,
1718 						&tmp[index], 1) < 0) {
1719 				dst->ret = -EIO;
1720 				return;
1721 			}
1722 	}
1723 }
1724 
1725 #define ELF_FP_OFFSET(i)	(i * sizeof(elf_fpreg_t))
1726 
1727 void do_fpregs_get(struct unw_frame_info *info, void *arg)
1728 {
1729 	struct regset_getset *dst = arg;
1730 	struct task_struct *task = dst->target;
1731 	elf_fpreg_t tmp[30];
1732 	int index, min_copy, i;
1733 
1734 	if (unw_unwind_to_user(info) < 0)
1735 		return;
1736 
1737 	/* Skip pos 0 and 1 */
1738 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1739 		dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1740 						      &dst->u.get.kbuf,
1741 						      &dst->u.get.ubuf,
1742 						      0, ELF_FP_OFFSET(2));
1743 		if (dst->count == 0 || dst->ret)
1744 			return;
1745 	}
1746 
1747 	/* fr2-fr31 */
1748 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1749 		index = (dst->pos - ELF_FP_OFFSET(2)) / sizeof(elf_fpreg_t);
1750 
1751 		min_copy = min(((unsigned int)ELF_FP_OFFSET(32)),
1752 				dst->pos + dst->count);
1753 		for (i = dst->pos; i < min_copy; i += sizeof(elf_fpreg_t),
1754 				index++)
1755 			if (unw_get_fr(info, i / sizeof(elf_fpreg_t),
1756 					 &tmp[index])) {
1757 				dst->ret = -EIO;
1758 				return;
1759 			}
1760 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1761 				&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1762 				ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1763 		if (dst->count == 0 || dst->ret)
1764 			return;
1765 	}
1766 
1767 	/* fph */
1768 	if (dst->count > 0) {
1769 		ia64_flush_fph(dst->target);
1770 		if (task->thread.flags & IA64_THREAD_FPH_VALID)
1771 			dst->ret = user_regset_copyout(
1772 				&dst->pos, &dst->count,
1773 				&dst->u.get.kbuf, &dst->u.get.ubuf,
1774 				&dst->target->thread.fph,
1775 				ELF_FP_OFFSET(32), -1);
1776 		else
1777 			/* Zero fill instead.  */
1778 			dst->ret = user_regset_copyout_zero(
1779 				&dst->pos, &dst->count,
1780 				&dst->u.get.kbuf, &dst->u.get.ubuf,
1781 				ELF_FP_OFFSET(32), -1);
1782 	}
1783 }
1784 
1785 void do_fpregs_set(struct unw_frame_info *info, void *arg)
1786 {
1787 	struct regset_getset *dst = arg;
1788 	elf_fpreg_t fpreg, tmp[30];
1789 	int index, start, end;
1790 
1791 	if (unw_unwind_to_user(info) < 0)
1792 		return;
1793 
1794 	/* Skip pos 0 and 1 */
1795 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1796 		dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1797 						       &dst->u.set.kbuf,
1798 						       &dst->u.set.ubuf,
1799 						       0, ELF_FP_OFFSET(2));
1800 		if (dst->count == 0 || dst->ret)
1801 			return;
1802 	}
1803 
1804 	/* fr2-fr31 */
1805 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1806 		start = dst->pos;
1807 		end = min(((unsigned int)ELF_FP_OFFSET(32)),
1808 			 dst->pos + dst->count);
1809 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1810 				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1811 				ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1812 		if (dst->ret)
1813 			return;
1814 
1815 		if (start & 0xF) { /* only write high part */
1816 			if (unw_get_fr(info, start / sizeof(elf_fpreg_t),
1817 					 &fpreg)) {
1818 				dst->ret = -EIO;
1819 				return;
1820 			}
1821 			tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0]
1822 				= fpreg.u.bits[0];
1823 			start &= ~0xFUL;
1824 		}
1825 		if (end & 0xF) { /* only write low part */
1826 			if (unw_get_fr(info, end / sizeof(elf_fpreg_t),
1827 					&fpreg)) {
1828 				dst->ret = -EIO;
1829 				return;
1830 			}
1831 			tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1]
1832 				= fpreg.u.bits[1];
1833 			end = (end + 0xF) & ~0xFUL;
1834 		}
1835 
1836 		for ( ;	start < end ; start += sizeof(elf_fpreg_t)) {
1837 			index = start / sizeof(elf_fpreg_t);
1838 			if (unw_set_fr(info, index, tmp[index - 2])) {
1839 				dst->ret = -EIO;
1840 				return;
1841 			}
1842 		}
1843 		if (dst->ret || dst->count == 0)
1844 			return;
1845 	}
1846 
1847 	/* fph */
1848 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) {
1849 		ia64_sync_fph(dst->target);
1850 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1851 						&dst->u.set.kbuf,
1852 						&dst->u.set.ubuf,
1853 						&dst->target->thread.fph,
1854 						ELF_FP_OFFSET(32), -1);
1855 	}
1856 }
1857 
1858 static int
1859 do_regset_call(void (*call)(struct unw_frame_info *, void *),
1860 	       struct task_struct *target,
1861 	       const struct user_regset *regset,
1862 	       unsigned int pos, unsigned int count,
1863 	       const void *kbuf, const void __user *ubuf)
1864 {
1865 	struct regset_getset info = { .target = target, .regset = regset,
1866 				 .pos = pos, .count = count,
1867 				 .u.set = { .kbuf = kbuf, .ubuf = ubuf },
1868 				 .ret = 0 };
1869 
1870 	if (target == current)
1871 		unw_init_running(call, &info);
1872 	else {
1873 		struct unw_frame_info ufi;
1874 		memset(&ufi, 0, sizeof(ufi));
1875 		unw_init_from_blocked_task(&ufi, target);
1876 		(*call)(&ufi, &info);
1877 	}
1878 
1879 	return info.ret;
1880 }
1881 
1882 static int
1883 gpregs_get(struct task_struct *target,
1884 	   const struct user_regset *regset,
1885 	   unsigned int pos, unsigned int count,
1886 	   void *kbuf, void __user *ubuf)
1887 {
1888 	return do_regset_call(do_gpregs_get, target, regset, pos, count,
1889 		kbuf, ubuf);
1890 }
1891 
1892 static int gpregs_set(struct task_struct *target,
1893 		const struct user_regset *regset,
1894 		unsigned int pos, unsigned int count,
1895 		const void *kbuf, const void __user *ubuf)
1896 {
1897 	return do_regset_call(do_gpregs_set, target, regset, pos, count,
1898 		kbuf, ubuf);
1899 }
1900 
1901 static void do_gpregs_writeback(struct unw_frame_info *info, void *arg)
1902 {
1903 	do_sync_rbs(info, ia64_sync_user_rbs);
1904 }
1905 
1906 /*
1907  * This is called to write back the register backing store.
1908  * ptrace does this before it stops, so that a tracer reading the user
1909  * memory after the thread stops will get the current register data.
1910  */
1911 static int
1912 gpregs_writeback(struct task_struct *target,
1913 		 const struct user_regset *regset,
1914 		 int now)
1915 {
1916 	if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
1917 		return 0;
1918 	set_notify_resume(target);
1919 	return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
1920 		NULL, NULL);
1921 }
1922 
1923 static int
1924 fpregs_active(struct task_struct *target, const struct user_regset *regset)
1925 {
1926 	return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
1927 }
1928 
1929 static int fpregs_get(struct task_struct *target,
1930 		const struct user_regset *regset,
1931 		unsigned int pos, unsigned int count,
1932 		void *kbuf, void __user *ubuf)
1933 {
1934 	return do_regset_call(do_fpregs_get, target, regset, pos, count,
1935 		kbuf, ubuf);
1936 }
1937 
1938 static int fpregs_set(struct task_struct *target,
1939 		const struct user_regset *regset,
1940 		unsigned int pos, unsigned int count,
1941 		const void *kbuf, const void __user *ubuf)
1942 {
1943 	return do_regset_call(do_fpregs_set, target, regset, pos, count,
1944 		kbuf, ubuf);
1945 }
1946 
1947 static int
1948 access_uarea(struct task_struct *child, unsigned long addr,
1949 	      unsigned long *data, int write_access)
1950 {
1951 	unsigned int pos = -1; /* an invalid value */
1952 	int ret;
1953 	unsigned long *ptr, regnum;
1954 
1955 	if ((addr & 0x7) != 0) {
1956 		dprintk("ptrace: unaligned register address 0x%lx\n", addr);
1957 		return -1;
1958 	}
1959 	if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) ||
1960 		(addr >= PT_R7 + 8 && addr < PT_B1) ||
1961 		(addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) ||
1962 		(addr >= PT_AR_SSD + 8 && addr < PT_DBR)) {
1963 		dprintk("ptrace: rejecting access to register "
1964 					"address 0x%lx\n", addr);
1965 		return -1;
1966 	}
1967 
1968 	switch (addr) {
1969 	case PT_F32 ... (PT_F127 + 15):
1970 		pos = addr - PT_F32 + ELF_FP_OFFSET(32);
1971 		break;
1972 	case PT_F2 ... (PT_F5 + 15):
1973 		pos = addr - PT_F2 + ELF_FP_OFFSET(2);
1974 		break;
1975 	case PT_F10 ... (PT_F31 + 15):
1976 		pos = addr - PT_F10 + ELF_FP_OFFSET(10);
1977 		break;
1978 	case PT_F6 ... (PT_F9 + 15):
1979 		pos = addr - PT_F6 + ELF_FP_OFFSET(6);
1980 		break;
1981 	}
1982 
1983 	if (pos != -1) {
1984 		if (write_access)
1985 			ret = fpregs_set(child, NULL, pos,
1986 				sizeof(unsigned long), data, NULL);
1987 		else
1988 			ret = fpregs_get(child, NULL, pos,
1989 				sizeof(unsigned long), data, NULL);
1990 		if (ret != 0)
1991 			return -1;
1992 		return 0;
1993 	}
1994 
1995 	switch (addr) {
1996 	case PT_NAT_BITS:
1997 		pos = ELF_NAT_OFFSET;
1998 		break;
1999 	case PT_R4 ... PT_R7:
2000 		pos = addr - PT_R4 + ELF_GR_OFFSET(4);
2001 		break;
2002 	case PT_B1 ... PT_B5:
2003 		pos = addr - PT_B1 + ELF_BR_OFFSET(1);
2004 		break;
2005 	case PT_AR_EC:
2006 		pos = ELF_AR_EC_OFFSET;
2007 		break;
2008 	case PT_AR_LC:
2009 		pos = ELF_AR_LC_OFFSET;
2010 		break;
2011 	case PT_CR_IPSR:
2012 		pos = ELF_CR_IPSR_OFFSET;
2013 		break;
2014 	case PT_CR_IIP:
2015 		pos = ELF_CR_IIP_OFFSET;
2016 		break;
2017 	case PT_CFM:
2018 		pos = ELF_CFM_OFFSET;
2019 		break;
2020 	case PT_AR_UNAT:
2021 		pos = ELF_AR_UNAT_OFFSET;
2022 		break;
2023 	case PT_AR_PFS:
2024 		pos = ELF_AR_PFS_OFFSET;
2025 		break;
2026 	case PT_AR_RSC:
2027 		pos = ELF_AR_RSC_OFFSET;
2028 		break;
2029 	case PT_AR_RNAT:
2030 		pos = ELF_AR_RNAT_OFFSET;
2031 		break;
2032 	case PT_AR_BSPSTORE:
2033 		pos = ELF_AR_BSPSTORE_OFFSET;
2034 		break;
2035 	case PT_PR:
2036 		pos = ELF_PR_OFFSET;
2037 		break;
2038 	case PT_B6:
2039 		pos = ELF_BR_OFFSET(6);
2040 		break;
2041 	case PT_AR_BSP:
2042 		pos = ELF_AR_BSP_OFFSET;
2043 		break;
2044 	case PT_R1 ... PT_R3:
2045 		pos = addr - PT_R1 + ELF_GR_OFFSET(1);
2046 		break;
2047 	case PT_R12 ... PT_R15:
2048 		pos = addr - PT_R12 + ELF_GR_OFFSET(12);
2049 		break;
2050 	case PT_R8 ... PT_R11:
2051 		pos = addr - PT_R8 + ELF_GR_OFFSET(8);
2052 		break;
2053 	case PT_R16 ... PT_R31:
2054 		pos = addr - PT_R16 + ELF_GR_OFFSET(16);
2055 		break;
2056 	case PT_AR_CCV:
2057 		pos = ELF_AR_CCV_OFFSET;
2058 		break;
2059 	case PT_AR_FPSR:
2060 		pos = ELF_AR_FPSR_OFFSET;
2061 		break;
2062 	case PT_B0:
2063 		pos = ELF_BR_OFFSET(0);
2064 		break;
2065 	case PT_B7:
2066 		pos = ELF_BR_OFFSET(7);
2067 		break;
2068 	case PT_AR_CSD:
2069 		pos = ELF_AR_CSD_OFFSET;
2070 		break;
2071 	case PT_AR_SSD:
2072 		pos = ELF_AR_SSD_OFFSET;
2073 		break;
2074 	}
2075 
2076 	if (pos != -1) {
2077 		if (write_access)
2078 			ret = gpregs_set(child, NULL, pos,
2079 				sizeof(unsigned long), data, NULL);
2080 		else
2081 			ret = gpregs_get(child, NULL, pos,
2082 				sizeof(unsigned long), data, NULL);
2083 		if (ret != 0)
2084 			return -1;
2085 		return 0;
2086 	}
2087 
2088 	/* access debug registers */
2089 	if (addr >= PT_IBR) {
2090 		regnum = (addr - PT_IBR) >> 3;
2091 		ptr = &child->thread.ibr[0];
2092 	} else {
2093 		regnum = (addr - PT_DBR) >> 3;
2094 		ptr = &child->thread.dbr[0];
2095 	}
2096 
2097 	if (regnum >= 8) {
2098 		dprintk("ptrace: rejecting access to register "
2099 				"address 0x%lx\n", addr);
2100 		return -1;
2101 	}
2102 #ifdef CONFIG_PERFMON
2103 	/*
2104 	 * Check if debug registers are used by perfmon. This
2105 	 * test must be done once we know that we can do the
2106 	 * operation, i.e. the arguments are all valid, but
2107 	 * before we start modifying the state.
2108 	 *
2109 	 * Perfmon needs to keep a count of how many processes
2110 	 * are trying to modify the debug registers for system
2111 	 * wide monitoring sessions.
2112 	 *
2113 	 * We also include read access here, because they may
2114 	 * cause the PMU-installed debug register state
2115 	 * (dbr[], ibr[]) to be reset. The two arrays are also
2116 	 * used by perfmon, but we do not use
2117 	 * IA64_THREAD_DBG_VALID. The registers are restored
2118 	 * by the PMU context switch code.
2119 	 */
2120 	if (pfm_use_debug_registers(child))
2121 		return -1;
2122 #endif
2123 
2124 	if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
2125 		child->thread.flags |= IA64_THREAD_DBG_VALID;
2126 		memset(child->thread.dbr, 0,
2127 				sizeof(child->thread.dbr));
2128 		memset(child->thread.ibr, 0,
2129 				sizeof(child->thread.ibr));
2130 	}
2131 
2132 	ptr += regnum;
2133 
2134 	if ((regnum & 1) && write_access) {
2135 		/* don't let the user set kernel-level breakpoints: */
2136 		*ptr = *data & ~(7UL << 56);
2137 		return 0;
2138 	}
2139 	if (write_access)
2140 		*ptr = *data;
2141 	else
2142 		*data = *ptr;
2143 	return 0;
2144 }
2145 
2146 static const struct user_regset native_regsets[] = {
2147 	{
2148 		.core_note_type = NT_PRSTATUS,
2149 		.n = ELF_NGREG,
2150 		.size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t),
2151 		.get = gpregs_get, .set = gpregs_set,
2152 		.writeback = gpregs_writeback
2153 	},
2154 	{
2155 		.core_note_type = NT_PRFPREG,
2156 		.n = ELF_NFPREG,
2157 		.size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t),
2158 		.get = fpregs_get, .set = fpregs_set, .active = fpregs_active
2159 	},
2160 };
2161 
2162 static const struct user_regset_view user_ia64_view = {
2163 	.name = "ia64",
2164 	.e_machine = EM_IA_64,
2165 	.regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
2166 };
2167 
2168 const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
2169 {
2170 	return &user_ia64_view;
2171 }
2172 
2173 struct syscall_get_set_args {
2174 	unsigned int i;
2175 	unsigned int n;
2176 	unsigned long *args;
2177 	struct pt_regs *regs;
2178 	int rw;
2179 };
2180 
2181 static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
2182 {
2183 	struct syscall_get_set_args *args = data;
2184 	struct pt_regs *pt = args->regs;
2185 	unsigned long *krbs, cfm, ndirty;
2186 	int i, count;
2187 
2188 	if (unw_unwind_to_user(info) < 0)
2189 		return;
2190 
2191 	cfm = pt->cr_ifs;
2192 	krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8;
2193 	ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
2194 
2195 	count = 0;
2196 	if (in_syscall(pt))
2197 		count = min_t(int, args->n, cfm & 0x7f);
2198 
2199 	for (i = 0; i < count; i++) {
2200 		if (args->rw)
2201 			*ia64_rse_skip_regs(krbs, ndirty + i + args->i) =
2202 				args->args[i];
2203 		else
2204 			args->args[i] = *ia64_rse_skip_regs(krbs,
2205 				ndirty + i + args->i);
2206 	}
2207 
2208 	if (!args->rw) {
2209 		while (i < args->n) {
2210 			args->args[i] = 0;
2211 			i++;
2212 		}
2213 	}
2214 }
2215 
2216 void ia64_syscall_get_set_arguments(struct task_struct *task,
2217 	struct pt_regs *regs, unsigned int i, unsigned int n,
2218 	unsigned long *args, int rw)
2219 {
2220 	struct syscall_get_set_args data = {
2221 		.i = i,
2222 		.n = n,
2223 		.args = args,
2224 		.regs = regs,
2225 		.rw = rw,
2226 	};
2227 
2228 	if (task == current)
2229 		unw_init_running(syscall_get_set_args_cb, &data);
2230 	else {
2231 		struct unw_frame_info ufi;
2232 		memset(&ufi, 0, sizeof(ufi));
2233 		unw_init_from_blocked_task(&ufi, task);
2234 		syscall_get_set_args_cb(&ufi, &data);
2235 	}
2236 }
2237